What is the difference between SPXO and XO?

SPXO are different from conventional crystal oscillator(XO )?in that they have different output signals.

Output of SPXO

LVPECL, LVDS, and HCSL are common output signals for SPXO, LVPECL and LVDS have been used in major differential systems for a long time.

SPXO is a two lines transmission that outputs a set of signals with the same amplitude but opposite phase.?The receiving end judges the logical state based on the voltage difference of the signal.?

Therefore, in high-speed communication, the anti-interference characteristics of SPXO signals are superior to conventional XO.

Output of XO

TTL and HCMOS(CMOS) are output for conventional crystal oscillator.?

Due to being a single line output, it is convenient for wiring arrangement, but the disadvantage is poor anti-interference ability,?which is not suitable for high-speed information (above 100MHz)

So what is the difference in the circuit working principle?

LVPECL that is, Low Voltage PosiTIve Emitter-Couple Logic, that is, low-voltage positive emitter-coupled logic,?using a 3.3V or 2.5V power supply. PECL is PosiTIve Emitter-Couple Logic, which means positive emitter-couple logic,?and uses a 5.0V power supply coupled logic.

The circuit is a non-saturated digital logic circuit in which the transistors operate in the linear or cutoff region,?and the speed is not limited by the storage time of a few carriers.?So it is one of the fastest logic circuits available and can meet the operating rate of up to 10 Gbps.?

PECL/LVPECL is more widely used than ECL because PECL/LVPECL can share a positive power supply with other circuits in the system.?

Initially, PECL devices connected VCC to +5V, but later LVPECL (Low Voltage PECL) with VCC=3.3V/2.5V emerged to directly utilize the widely used 3.3V and 2.5V voltages.

LVDS signaling generally consists of three parts: differential signal transmitter, differential signal interconnector, and differential signal receiver, and is a low-amplitude differential signaling technology?that allows signals to be transmitted at hundreds of Mbps over differential PCB pairs?or balanced cables with low amplitude and low current drive outputs for low noise and low power consumption.?

In conclusion:

1. conventional crystal oscillator is 4pins ,SPXO is 6pins
2. Output is difference. XO is?Single ended output, ,SPXO is differential output
3. Different applications, XO is more suitbale for <100MHz , SPXO is more better for >100MHz
4. The anti-interference ability also varies
5. Of course, SPXO price is more higher than XO.